Annual report of the Australian National Poliovirus Reference Laboratory and summary of acute flaccid paralysis surveillance, 2001

Abstract

The National Poliovirus Reference Laboratory at the Victorian Infectious Diseases Reference Laboratory (VIDRL) is responsible for poliovirus testing for Australia and the Pacific Island countries. It is also a regional reference laboratory for the Western Pacific Region of the World Health Organization. Surveillance for acute flaccid paralysis, a clinical manifestation of poliomyelitis, is coordinated at VIDRL in collaboration with the Australian Paediatric Surveillance Unit. There were 60 unique notifications of acute flaccid paralysis (AFP) in 2001, of which 44 were classified by the polio expert committee as eligible non-polio AFP cases, that is, from patients resident in Australia and aged less than 15 years. Polioviruses were Isolated from one AFP patient and characterised as Sabin oral poliovirus vaccine-like for all 3 serotypes. In the same period, the National Poliovirus Reference Laboratory identified 40 Sabin-like viruses from 74 referred isolates and specimens, and an additional five non-Sabin-like polioviruses as part of the laboratory containment of poliovirus. The Western Pacific Region, of which Australia is a member nation, was declared free of circulating wild poliovirus in October 2000. However, during 2001, viruses derived from the Sabin oral poliovirus vaccine caused 3 cases of poliomyelitis in the Philippines, also a member nation of the Western Pacific Region. The identification of circulating vaccine-derived poliovirus in the Philippines has emphasised the necessity of maintaining a high level of vaccination coverage within Australia and an effective surveillance system to detect cases of poliomyelitis.